Astronomers have discovered the largest single structure in the universe, a collection of quasars which form a single entity; and it is terrifyingly large.

The universe is filled with massive things, but none quite as massive as what an international team of scientists have just discovered. The team has discovered a collection of 73 quasars, which are grouped together to form a single structure. A quasar is the brightly luminous nucleus of a galaxy, which in the 1980's was discovered to mainly consist of a gas layer surrounding a super massive black hole. In other words, the structure is a massive grouping of black holes. The structure is at it's widest a whopping 4 billion light years across, which is about 1,600 times the distance between our galaxy and the neighboring Andromeda galaxy. The milky way itself is only about 100,000-120,000 light years across.

Artist's rendering of a quasar

"While it is difficult to fathom the scale of this large quasar group, we can say quite definitely it is the largest structure ever seen in the entire universe. This is hugely exciting – not least because it runs counter to our current understanding of the scale of the universe." explains Dr. Clowes, a researcher on the team that discovered the Quasar group. Indeed, Clowes goes on to explain that the structure is so large that it challenges the cosmological principle, the notion that on a large enough scale, the properties of the universe are the same for all observers.